Cassarino, the former mayor and board president who rejoined the board last year after several years away from city politics, wrote that he had "been distracted by some unexpected medical and physical problems, as well as some important family obligations," rendering him unable to devote the appropriate time and energy to the position.

Should the board accept his resignation when it next meets, it will fall to Mayor Christopher Louras to appoint someone to fill out the remainder of the two-year term.